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Mohamad Reza Setare

Mohamad Reza Setare

Academic rank: Professor
ORCID:
Education: PhD.
ScopusId: 7003669033
HIndex:
Faculty: Faculty of Science
Address:
Phone: 08716660075

Research

Title
Tachyon warm-logamediate inflationary universe model in a high dissipative regime
Type
JournalPaper
Keywords
Tachyon warm, inflationary universe model
Year
2013
Journal PHYSICAL REVIEW D
DOI
Researchers Mohamad Reza Setare ، Vahid Kamali

Abstract

In the present work, we study the warm tachyon inflation model in the context of ‘‘logamediate inflation,’’ where the smological scale factor expands as a ¼ a0 exp ðA½ln tÞ. The characteristics of this model in slow-roll approximation are presented in the following two cases: (1) The dissipative-parameter  is a function of the tachyon field  and (2)  is a constant parameter. The level of non-Gaussianity of this model is found for these two cases. Scalar and tensor perturbations for this scenario are presented. The parameters appearing in our model are constrained by recent observational data (WMAP7). Harrison-Zeldovich spectrum, i.e., ns ¼ 1, is approximately obtained for large values of (i.e.,  ’ 50) and for normal values of the number of e-folds, i.e., N ’ 60. On the other hand, the scale invariant spectrum (Harrison-Zeldovich spectrum) is given by using two parameters in our model. For intermediate inflation, where the cosmological scale factor expands as a ¼ a0 exp ðAtfÞ, this spectrum has been exactly obtained using one parameter, i.e., f ¼ 23 M. R. Setare and V. Kamali, J. Cosmol. Astropart. Phys. 08 (2012) 034.